Bathymetry and topography of the Sumatran
plate boundary shows the arcuate subduction zone cropping out
on the seafloor at about 5 km depth (pale against dark blue)
and the Great Sumatran fault coursing through the mountainous,
volcanic backbone of the island. Topographic data is
from NASA’s SRTM. View is toward the southeast.

The
Sumatran Plate Boundary Projectis a multi disciplinary effort to understand tectonic processes
at a plate boundary dominated by the oblique convergence of oceanic
and continental plates. Thus far, we have been mapping the
principal active structures, conducting paleoseismologic and paleogeodetic
research, monitoring strains with a continuous
GPS network, and modeling these data.The Sumatran Plate Boundary
is a clear example of a slip-partitioned system: The vertical component
of convergence is accommodated principally across the Sumatran
subduction zone and most of the horizontal component of convergence
is taken up across the Great Sumatran
fault.Rupture of the subduction zone has produced earthquakes
as large magnitude 9. Earthquakes with magnitudes up to about
7.5 are common along the Great Sumatran Fault.